Not starting a fight but would like to nail this down.
So which one of the following describes the headset type in a Giant OCR Composite frame?
Thanks,
Eddie
"Low Profile", "Zero Stack", "Intergrated with Cups", "Internal Headset", "Semi-Intergrated" types
This type of headset system has, unfortunately, several names. Cane Creek® uses ZS or Zero Stack, while FSA® uses the Orbit Z series. The low-profile, zero-stack, integrated-with-cups, semi-intergrated, or internal-headset systems use pressed frame cups that act as a holder for the bearings. The cups have a flange, or lip, and sit adjacent to the outer edge of the top and bottom of the headtube. The headtube is a relatively large outside diameter, approximately 50mm, and cups allow the bearings to sit flush or even inside the headtube. The headset bearings sit "internally" to the top and bottom of the headtube. Some models use a cup that holds a cartridge bearing. The cartridge bearing is a slip fit into the cups. The cups act as a bearing holder and do not take bearing movement or wear directly. Other types have the cartridge bearing and cup/holder as a unit. These are simply replaced as a unit when it is worn out. Still another version of this type uses a cup and cone system with caged ball bearings, similar to the conventional threadless headsets. Additionally, the depth of insertion into the headtube will vary between brands and type. If the bike was designed for a shallow cup, a deeper cup will not properly fit. This lack of consensus in depth makes reaming the inside of the headtube problematic.
or this:
Integrated- Angular Contact System (without cups)
The integrated system uses cartridge bearings that are supported by machining in a specially shaped head tube. The frame may also use pressed rings or retainers inside the headtube. A cartridge bearing slips into these "cups" or supports, and is simply lifted out for replacement. There is no contact with the headtube face. The bearing sits inside the headtube, and references the angular contact. There are different standards within this integrated-angular contact family, and these are not interchangeable. A table at the end of this article summarizes the various standards.
The "IS" system is considered the most common. The name Integrated System is not a registered trade name. The system uses the 45-degree bearing contact in the frame. The bearings for the 1-1/8 inch steering columns use a 41mm outside diameter with a 45-degree bearing contact in the frame. The bearing may be marked "36-45". The first number refers to the inside bearing contact with the headset race or centering cone. The second number refers to the frame contact.
The less common 36-degree angular contact standard uses a bearing for the 1-1/8 inch steering columns with a 41.5mm outside diameter. The bearings may be marked "36-36".